Even after a loss, Alistair Overeem is the source of controversy. Ben Rothwell knocked out "The Reem" in the first round during the co-main event of UFC Fight Night 50 on Friday, but he wasn't happy with some of Overeem's fighting tactics.

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"I almost yelled at him in the fight," Rothwell told Submission Radio on Monday. "He was doing some real dirty push kicks to my knee, and it's just a dirty move. It's not honorable in my mind because this isn't street fighting."

The "oblique kick," as it's known, is a signature technique used by UFC light heavyweight champion Jon Jones and many fighters view it as a dirty move because it aims to hyperextend the opponent's knee. It was expected that Overeem would incorporate new techniques since moving his fight camp to Jackson's MMA in Albuquerque, NM, where Jones trains.

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The move is still legal in mixed martial arts, but Rothwell isn't the first fighter to speak out against the technique. Former UFC light heavyweight champion Quinton "Rampage" Jackson said the oblique kick should be banned from competition and called Jones one of the dirtiest opponents he's ever fought after he did serious damage to his knees in their 2011 bout.

"It's like, you don't do that," Rothwell said. "And I almost said something to him during the fight like 'really?' like 'you're gonna play like that?' and I luckily ended him before he got to do it anymore."